Air-compressor



(No Model.)

E. HILL.

Air Compressor.

No. 243,257; Patented June 21,1881.

UNITED STATES PATENT OFFICE,

EBENEZER HILL, OF SOUTH NORWALK, CONNECTICUT.

AIR-COMPRESSOR.

SPECIFICATION forming part of Letters Patent No. 243,257, dated June 21, 1881.

Application filed February 24, 1881. (No model.)

To all whom it may concern:

Be it known that I, EBENEZER HILL, of South Norwalk, in the county of Fairfield and State of Connecticut, have invented new and useful Improvements in Air-Compressors, of which the following is a specification.

This invention pertains to certain improvements in air-compressors where a steam-engine is combined with an air-compressing engine, and with atly wheel or wheels mounted on a shaft carrying two cranks, and connected to a cross-head to which the pistons of the steamengine and air-compressor are attached; and the invention consists in connecting the extremities of the cross-head to cranks that are on opposite sides of a plane passing longitudinally through the axis, but at a less distance than a right angle to each other, and having connecting-rods of equal length and with balland-socket connections, so that as the cranks revolve the cross-head will be vibrated upon its pivoted connection with the engine-piston, and thereby give variable movements to the air-compressing piston and varying in degree to the angle which the cranks bear to each other, the object being to increase the speed of the air-compression piston at the beginning of its stroke and to diminish it at the end or as itapproaches the end, where ithas the greatest amount of work-to do, as will hereinafter appear.

In the drawings, Figures 1 and 2 are plans of the apparatus, as above specified, showing the engines at nearly opposite points in their stroke.

At A is represented the bed-frame of the machine, upon which is mounted the steam cylinder or engine, at B, and air-compressor C, both of which are connected to the cross-head D by links, as at E, and said cross-head is connected to crank-pins on the fly-wheels, as at F and F, by connecting-rods, as at G and G, which have spherical boxes at each end,'as shown, to permit the cross -head to swivel or vibrate according to the positions of the crank-pins relatively to aplane passing longitudinally through the main shafts at H, upon which the fiy-wheels are mounted.

Under such a construction, if the steam-piston in the cylinder at B in Fig. 1 begins to 'move in the direction of the arrows, the piston of the air-cylinder will be moved in advance on account of its crank-pin at F being placed in advance of the other at F; but after they have passed their centers and enter upon the next half of their revolution, or as represented at Fig. 2, when the steam-piston has nearly completed its stroke, then the reverse movement takes place and the air-compressingpiston moves slower or is retarded, so that its movement is varied to a certain extent, according to the work. Another advantage of such an arrangement is that thedead air in the cylinders of the compressors will react to force the cross-head back, and thus serves to assist in working the engine when the steam-piston or crank is on its center, and therefore said power is not lost.

It is evident that the engines may be arranged on opposite sides of the cross-head in place of the same side, as shown in the drawings.

It may also be remarked that two aircompressing engines maybe connected to the crosshead, and also that motion may be given to the cross-head by a pulley or gearing on the main shaft, or in other convenient manner, and at the same time have all the advantages of the vibrating or swiveling cross-head, as hereinbefore set forth.

It is also evident that the connecting-rods need not necessarily be of equal lengths in such a combination, as they will thereby serve as a substitue for the unequal arrangement of the cranks.

I therefore claim-- In an air-compressing apparatus, the combination of a steam-engine and an air-compressing engine with a cross-head, which is connected at its extremities by spherical bearings and connecting-rods to cranks on opposite sides of a plane through the main shaft and at an angle to said plane less than a right an gle, as and for the purpose hereinbefore set forth.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

EBENEZER HILL.

Witnesses:

O. J. HILL, CHAS. BARTRAM. 

